Some questions... I planning to make a very large LED-wall of sorts made up

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Some questions…

I planning to make a very large LED-wall of sorts made up of individual panels of LEDs.

I’ve done a lot of Googling for my project, but I still can’t figure some things out:

  1. How many milliamps does a WS2812B actually draw at full brightness white? I’m not planning to do this, but I’d like my power supplies to be capable of it when running at the tip of 100%.
  2. How many pins can I use for parallel output on a Teensy 3.2? How many LEDs maximum per pin can I use to achieve around 400 to 500 fps? To make my life simpler, I’d like to use the maximum amount of LEDs per one or two data lines per panel (instead of splitting it up). The panels will be in parallel, not in series.
  3. How far can the data line go (over CAT 5e for example) before the first LED?
  4. Will having data wires of different lengths affect the response times between different panels?
  5. If I use multiple Teensies, should I have some sort of clock running in between them? They will be receiving data from the computer simultaneously, but should I implement a clock separately?
  6. What is the largest known FastLED installation?

Thanks!

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Have you already read up on the OctoWS2811 Adaptor? https://www.pjrc.com/store/octo28_adaptor.html Even if you don’t use the actual adaptor (although I highly recommend it), there’s lots of good information there.

Have you already built a smaller panel? I highly recommend starting small and working your way up to larger projects.

As for your questions:

  1. Each LED draws about 60mA at full brightness white.
  2. You can run 8 in parallel on the Teensy 3.2: https://github.com/FastLED/FastLED/wiki/Parallel-Output
    3 - 6. I think most, if not all of these are answered on the OctoWS2811 page.
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Thanks for the reply! That page did have a lot of good info. I also just stumbled upon these pages:
https://forum.pjrc.com/threads/15620-WS2811-on-Teensy-3-0-using-FastSPI_LED-library?p=24000&viewfull=1#post24000
https://www.pjrc.com/teensy/td_libs_OctoWS2811.html

I know that I can run 8 in parallel, but how many lights maximum per pin? I’d like to achieve somewhere around 400 or 500Hz. The wiki page says 64 per pin, but has anything higher been tested?

Right now I’m looking into custom-fabbing 16x16 pixel panels and arrangning then 8x6 (4:3 aspect ratio), for a total of 128x96 pixels, or 12,288 LEDs. Each panel will be split between a Teensy, adding up to 24 Teensies. I will most likely also fab boards for the Teensies to sit in.

If I run them at half power, it should be manageable. I’ve found some power supplies on Alibaba/AliExpress, but I find some of them to be a bit sketchy. Does anyone know of a for-sure reputable one that can output at least 50 amps?

The forum post I linked to above has create instructions on the frame syncing for a plethora of Teensies. However, that is using the OctoWs2811 library. The wiki page for parallel FastLED mentions using FastLED with OctoWS2811. Can I use FastLED with dithering and color correction alongside OctoWS2811 and the framesync pin?

Also, how exactly does the framesync work with so many Teensies? Does the first simply send the signal to the others or is there some bidirectional communication between them?

Thanks for reading my questions!